Brunharo Caio A C G, Streisfeld Matthew A
Department of Crop and Soil Science Oregon State University Corvallis Oregon USA.
Institute of Ecology and Evolution University of Oregon Eugene Oregon USA.
Evol Appl. 2022 Feb 8;15(2):316-329. doi: 10.1111/eva.13344. eCollection 2022 Feb.
The multitude of herbicide resistance patterns that have evolved in different weed species is a remarkable example of the rapid adaptation to anthropogenic-driven disturbance. Recently, resistance to glyphosate was identified in multiple populations of in Oregon. We used phenotypic approaches, as well as population genomic and gene expression analyses, to determine whether known mechanisms were responsible for glyphosate resistance and whether resistance phenotypes evolved independently in different populations, and to identify potential loci contributing to resistance. We found no evidence of genetic alterations or expression changes at known target and non-target-site resistance mechanisms of glyphosate. Population genomic analyses indicated that resistant populations tended to have largely distinct ancestry from one another, suggesting that glyphosate resistance did not spread among populations by gene flow. Rather, resistance appears to have evolved independently on different genetic backgrounds. We also detected potential loci associated with the resistance phenotype, some of which encode proteins with potential effects on herbicide metabolism. Our results suggest that Oregon populations of . evolved resistance to glyphosate due to a novel mechanism. Future studies that characterize the gene or genes involved in resistance will be necessary to confirm this conclusion.
在不同杂草物种中进化出的多种除草剂抗性模式，是对人为干扰快速适应的一个显著例子。最近，在俄勒冈州的多个种群中发现了对草甘膦的抗性。我们采用表型方法以及群体基因组和基因表达分析，来确定已知机制是否导致草甘膦抗性，抗性表型是否在不同种群中独立进化，并识别有助于抗性的潜在基因座。我们没有发现草甘膦已知靶标和非靶标位点抗性机制发生遗传改变或表达变化的证据。群体基因组分析表明，抗性种群彼此之间往往有很大不同的祖先，这表明草甘膦抗性不是通过基因流动在种群间传播的。相反，抗性似乎是在不同的遗传背景上独立进化的。我们还检测到与抗性表型相关的潜在基因座，其中一些编码对除草剂代谢可能有影响的蛋白质。我们的结果表明，俄勒冈州的种群由于一种新机制而进化出对草甘膦的抗性。未来需要开展研究来鉴定参与抗性的一个或多个基因，以证实这一结论。
